JP4256117B2 - Method for producing titanium-based perovskite ceramic raw material powder - Google Patents

Description

【００７０】
比較例１〜３
ＢＥＴ比表面積が８．２ｍ^２／ｇ、１２．３ｍ^２／ｇの２種類の市販のＢａＣＯ_３粉末と、ＢＥＴ比表面積が７．７ｍ^２／ｇ、１８．４ｍ^２／ｇの２種類の市販のＴｉＯ_２粉末を用意した。次にＢａＣＯ_３とＴｉＯ_２がモル比で１対１になるようにこれらの原料粉末を秤量した。次に、表２に示したＢａＣＯ_３とＴｉＯ_２の組み合わせで、水およびジルコニアボール（１．５φ）とともにボールミル内に入れ、湿式で１５時間十分に混合し、得られたスラリーを乾燥機に入れ、１５０℃で乾燥し、混合粉体を得た。次に、乾燥品をロールミルで粉砕した。この粉砕品をシャトルキルンに装入し１１００℃で２４時間焼成した。次に、焼成物をロールミルで粉砕し、更にジェットミルで微粉砕して焼成品を得た。Ｘ線回折法により得られた焼成品はチタン酸バリウムであることを確認した。焼成品について、平均粒径ｘ、ＢＥＴ比表面積及び粒子径のバラツキσ／ｘを求めた。結果を表２に示す。
【００７１】
【表２】

【００７２】
表１及び表２の結果より、本発明に係る製造方法で得られるチタン系ペロブスカイト型セラミック原料粉末は、微細で且つ極めて粒度分布のバラツキが少ないことが分かる。
【００７３】
【発明の効果】
本発明に係るチタン系ペロブスカイト型セラミック原料粉末の製造方法によれば、微細で且つ極めて粒度分布のバラツキが少ないものを得ることができる。該チタン系ペロブスカイト型セラミック原料粉末は、機能性セラミック、特に薄膜化が要求されるセラミックシート等に好適に用いることができる。
【図面の簡単な説明】
【図１】ビーズミル装置の一例を模式的に示した図である。
【符号の説明】
１ ビーズミル装置
１ａ 回転筒（ベッセル）
１ｂ 攪拌羽根部
１ｃ ジルコニアビーズ
１ｄ メディア分離装置
１ｅ 攪拌羽根駆動部
１ｆ、１ｇ 導入口
１ｈ 排出口
２ 第一原料貯蔵槽
３ 第二原料貯蔵槽
４ 生成物貯蔵槽
Ｐ１、Ｐ２ ポンプ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a titanium-based perovskite ceramic raw material powder that is useful as a raw material for functional ceramics such as piezoelectric materials, optoelectronic materials, dielectric materials, semiconductors, and sensors. ₃ The present invention relates to a method for producing a titanium-based perovskite ceramic raw material powder in which Ca, Ba, Sr or Pb is arranged at the A site of the type perovskite and Ti is arranged at the B site.
[0002]
[Prior art]
Conventionally, ABO ₃ As a method for producing a type perovskite type ceramic raw material, the following methods are typically used.
(1) A method in which oxide powders of the respective component elements are mixed and the mixture is heated to a high temperature to perform a solid phase reaction.
(2) A method in which oxalic acid is dropped into an aqueous solution containing ions of each component element to coprecipitate each component element as oxalate, and the oxalate is thermally decomposed.
(3) A method in which a mixture of alkoxides of the respective component elements is hydrolyzed and coprecipitated, and the coprecipitated hydrolyzate is thermally decomposed.
[0003]
The method (1) is, for example, the raw material BaCO. ₃ Powder and TiO ₂ The powder is wet mixed, dried, fired at a temperature of about 900 to 1200 ° C., and BaCO ₃ Particles and TiO ₂ In this method, particles are chemically reacted with each other in a solid phase to obtain barium titanate powder. However, the raw material BaCO ₃ And TiO ₂ Is not uniformly mixed, a so-called non-uniform portion such as a portion with a large amount of Ba and a small amount of Ti or a portion with a small amount of Ba and a large amount of Ti is formed in the mixture. There is a problem that the particle growth of the barium titanate particles is different for each non-uniform portion, and the variation in the particle size of the generated barium titanate powder becomes large.
[0004]
In addition, since the coprecipitate obtained by the coprecipitation method (2) has a large particle size of several tens of μm, it tends to be an aggregate of hard agglomerated powder when fired, and the oxalic acid used in large quantities is reused. There is a problem that the cost increases because it is impossible.
[0005]
Furthermore, although the coprecipitation method (3) uses each component as an alkoxide, a product with good quality can be obtained, but there are problems such as an increase in production cost due to wastewater treatment and raw material circumstances.
[0006]
In response to these problems, for example, Japanese Patent Publication No. 5-27570 discloses a method for producing a titanium-based perovskite-type ceramic raw material with uniform quality and low cost, from Ca, Ba, Sr or Pb in which titanium oxide is dispersed. A method is disclosed in which at least one selected soluble metal salt aqueous slurry, an aqueous ammonium bicarbonate solution and ammonia are mixed and subjected to a precipitation reaction, followed by firing.
[0007]
[Problems to be solved by the invention]
However, even if the titanium-based perovskite-type ceramic raw material powder obtained by the above-described manufacturing method is used, the advanced composition required as a raw material for functional ceramics such as piezoelectric materials, optoelectronic materials, dielectric materials, semiconductors, and sensors in recent years There is a problem that the uniformity of the particle size and the small variation in particle size are not sufficiently satisfied.
[0008]
Accordingly, an object of the present invention is to provide a method for producing a titanium-based perovskite-type ceramic raw material powder that can produce a titanium-based perovskite-type ceramic powder that is fine and has little variation in particle size at a low cost.
[0009]
[Means for Solving the Problems]
In such a situation, the present inventor has obtained a predetermined titanium compound (a), a predetermined soluble metal salt (b), a precipitant that reacts with the soluble metal salt (b) to form a hardly soluble metal compound (d) ( c) and the granular medium (f) are brought into contact with each other in a state where the granular medium (f) flows at a high speed in water, and the precipitate is obtained by depositing the hardly soluble metal compound (d) on the particle surface of the titanium compound (a). When (e) was obtained and the precipitate (e) was fired, it was found that a fine titanium-based perovskite ceramic raw material powder with little variation in particle size was obtained, and the present invention was completed.
[0010]
That is, the present invention is selected from titanium oxide or hydrous titanium oxide. The compounding amount is 0.01 to 3 mol / L in terms of Ti. A titanium compound (a), a soluble metal salt (b) of at least one element selected from the group consisting of Ca, Ba, Sr and Pb, and a hardly soluble metal compound (B) reacting with the soluble metal salt (b) a precipitating agent (c) producing d); The particle size is 0.05 to 10 mm and the filling factor in the reactor is 40 to 95%. A first step of obtaining a precipitate (e) by bringing the granular medium (f) into contact with water in a state where the granular medium (f) flows at a high speed in water; and baking the precipitate (e) to form a titanium-based perovskite type The present invention provides a method for producing a titanium-based perovskite ceramic raw material powder, comprising a second step of obtaining a ceramic raw material powder.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
In the first step, the titanium compound (a), the soluble metal salt (b), the precipitant (c), and the granular medium (f) are contacted in a state where the granular medium (f) flows at high speed in water. And a precipitate (e) is obtained.
[0012]
The titanium compound (a) used in the present invention is titanium oxide or hydrous titanium oxide. Here, titanium oxide or hydrous titanium oxide means either or both of titanium oxide and hydrous titanium oxide. Examples of titanium oxide include titanium dioxide, titanium monoxide, and dititanium trioxide. In the present invention, hydrous titanium oxide means an intermediate product of titanium dioxide in the sulfuric acid method. Examples of such hydrous titanium oxide include metatitanic acid and orthotitanic acid. The particle size of the titanium compound is not particularly limited, but a fine one is preferable because the reactivity in the second step described later is high, and the average particle size obtained by the laser method is preferably 0.1 to 2 μm. More preferably, it is 0.1-1 μm. A titanium compound (a) can be used 1 type or in combination of 2 or more types.
[0013]
The soluble metal salt (b) used in the present invention is a soluble metal salt of at least one element selected from the group consisting of Ca, Ba, Sr and Pb. Here, the term “soluble” means soluble in water, and forms a solution in the presence of water. Examples of the soluble metal salt (b) include Ca, Ba, Sr or Pb hydroxides, nitrates, chlorides and sulfides. The soluble metal salt (b) can be used alone or in combination of two or more.
[0014]
The precipitating agent (c) used in the present invention reacts with the soluble metal salt (b) to produce the below-mentioned hardly soluble metal compound (d). Examples of the precipitant (c) include ammonium bicarbonate, ammonium carbonate, sodium carbonate, carbon dioxide, oxalic acid, ammonium oxalate, citric acid, sodium citrate, ammonium citrate, tartaric acid, sodium tartrate, and ammonium tartrate. Can be mentioned. The precipitant (c) can be used alone or in combination of two or more.
[0015]
In the present invention, the hardly soluble metal compound (d) produced by the reaction of the precipitant (c) and the soluble metal salt (b) comprises Ca, Ba, Sr and Pb contained in the soluble metal salt (b). It means a metal compound of at least one element selected from the group and hardly soluble. Here, sparingly soluble means sparingly soluble in water. Examples of the hardly soluble metal compound (d) include carbonate, oxalate, citrate, and tartrate of Ca, Ba, Sr or Pb. Further, the hardly soluble metal compound (d) may contain one or more of the above.
[0016]
In the present invention, as the granular medium (f), a high-speed flowable granular material having chemical resistance such as acid resistance and alkali resistance, water resistance, non-reactivity, ductility, and non-destructiveness is used. Here, non-reactive refers to a titanium compound (a), a soluble metal salt (b), a precipitant (c), a hardly soluble metal compound (d), a precipitate (e), and a soluble compound (g) described later. It means having no reactivity. Examples of such a granular medium (f) include ceramic beads and resin beads. Examples of the ceramic beads include zirconia beads, alumina beads, silica beads, silicon carbide, and silicon nitride.
[0017]
Examples of the shape of the granular medium (f) include a spherical shape, a spindle shape, a cylindrical shape, and an indefinite shape. Among these, when it is spherical, the titanium-based perovskite can be applied to the hardly soluble metal compound (d) deposited on the particle surface of the titanium compound (a) during high-speed flow with a substantially constant shearing force and frictional force. The type ceramic raw material powder is preferable because it is fine and the particle size variation is likely to be small.
[0018]
The particle size of the granular medium (f) is usually 0.05 to 10 mm, preferably 0.1 to 3 mm. If the diameter of the granular medium (f) is less than 0.05 mm, it is not preferable because mechanical separation of the granular medium (f) and the precipitate (e) in the same system by a media separation device tends to be difficult. On the other hand, when the diameter of the granular medium (f) exceeds 10 mm, it becomes difficult to obtain a fine titanium-based perovskite ceramic powder with little variation in particle size, and a high-speed fluidization process is required for a long time. It is not preferable because efficiency is likely to decrease. In the present invention, the granular medium (f) can be used alone or in combination of two or more thereof.
[0019]
In the first step, the titanium compound (a), the soluble metal salt (b), the precipitant (c), and the granular medium (f) are brought into contact with each other in a state where the granular medium (f) flows at high speed in water, A precipitate (e) is obtained.
[0020]
In the present invention, the state in which the granular medium (f) flows at a high speed means that the granular medium (f) has a maximum peripheral speed of 0.1 to 25 m / s, preferably 1 to 20 m / s. In addition, when the maximum peripheral speed is less than 0.1 m / s, the shearing force to the poorly soluble metal compound (d) on which the granular medium (f) precipitates is insufficient, and fine particles of the hardly soluble metal compound (d) This makes it difficult to obtain a titanium-based perovskite ceramic raw material powder in which a fine hardly soluble metal compound (d) is uniformly deposited on the particle surface of the titanium compound (a). Further, it is preferable that the maximum peripheral speed exceeds 25 m / s because the slurry containing the precipitate (e) is easily contaminated by the abrasion of the granular medium (f) itself and the energy efficiency of shearing force and frictional heat is likely to be reduced. Absent.
[0021]
In the present invention, the filling rate of the granular medium (f) in the reactor is usually 40 to 95%, preferably 60 to 95%, more preferably 70 to 90%. Here, the filling rate is the volume of a substantial space excluding high-speed flow means such as a stirrer among the spaces in the reactor in an empty state in which no water or granular medium (f) is charged. It means the ratio of the apparent volume of the granular medium (f). Here, the apparent volume refers to the volume occupied by the outer shape of the entire granular medium (f) including the space generated between the granular media (f). The apparent volume is, for example, the product of the height of the granular medium (f) and the bottom area of the cylindrical container when the granular medium (f) is naturally dropped and filled in the cylindrical container and the upper surface is leveled flat. Desired. When the filling rate of the granular medium (f) is within this range, it is preferable because the shearing force and frictional force of the granular medium (f) with respect to the hardly soluble metal compound (d) can be appropriately managed. On the other hand, if the filling rate exceeds 95%, a medium locking phenomenon occurs, resulting in an overload of the driving device. If the filling rate is less than 40%, the collision probability of the granular medium (f) is remarkably lowered, and the titanium-based perovskite. This is not preferable because the mold ceramic raw material powder is difficult to be miniaturized.
[0022]
In the present invention, contact means the state in which the titanium compound (a), the soluble metal salt (b), and the precipitating agent (c) are in contact with the granular medium (f) in water, that is, underwater. Means a state where the four members (a), (b), (c) and (f) are in contact with each other. The soluble metal salt (b) itself is usually a solid, and the precipitating agent (c) itself takes a solid, liquid, or gas form, but these are dissolved, mixed or dispersed in water. Take an embodiment. In the present invention, the contact in the form after being dissolved in water in this way is also referred to as contact of the soluble metal salt (b) or the precipitant (c) in water.
[0023]
The mixing order of the titanium compound (a) and the like at the time of contacting is not particularly limited. For example, the titanium compound (a), the soluble metal salt (b), and the granular medium (f) are mixed to form a slurry. Thereafter, the slurry and the precipitating agent (c) are brought into contact with each other in a state where the granular medium (f) flows at high speed in water, and (a), (b), (c), (f) and water are added. The order etc. which mix simultaneously so that a granular medium (f) may be in the state which flows at high speed in water are mentioned.
[0024]
Among these, after preparing the slurry (henceforth "the A liquid") containing a titanium compound (a) and soluble metal salt (b), A liquid and a granular medium (f) are mixed, and this liquid mixture When the order of adding the precipitant (c) to the mixture is made after the granular medium (f) is in a state of flowing at high speed, the hardly soluble metal compound (d) to be produced becomes a particle surface of the titanium compound (a). This is preferable because a high-purity ceramic raw material powder uniformly adhered to the surface can be obtained. Also, an aqueous solution containing the precipitating agent (c) (hereinafter also referred to as “liquid B”) is prepared, the liquid A and the granular medium (f) are mixed, and the granular liquid (f) is mixed at high speed. The order in which the liquid B is added to the mixed solution after it is made to flow is more preferable since the reaction operability becomes easy.
[0025]
The amount of titanium compound (a), etc. with respect to the total amount of water, titanium compound (a), soluble metal salt (b) and precipitating agent (c) at the time of contact is such that the amount of titanium compound (a) is Ti The amount is usually 0.01 to 3 mol / L, preferably 0.1 to 2 mol / L. In addition, the compounding amount of the soluble metal salt (b) relative to the total amount of the titanium compound (a), etc. is the mole converted to Ca, Ba, Sr or Pb actually contained in the soluble metal salt (b). The total number of numbers is usually 0.01 to 3 mol / L, preferably 0.1 to 2 mol / L. Moreover, the compounding quantity of the precipitant (c) with respect to the total amount of the said titanium compound (a) etc. is 0.01-5 mol / L normally, Preferably it is 0.1-3 mol / L.
[0026]
Moreover, when performing a contact using A liquid or B liquid, the compounding quantity of the titanium compound (a) in A liquid is 0.01-3 mol / L normally in conversion of Ti, Preferably it is 0.1 -1.7 mol / L. Moreover, the compounding quantity of the soluble metal salt (b) in A liquid is the total amount converted into what is contained in soluble metal salt (b) among Ca, Ba, Sr, or Pb normally 0.01-3. Mol / L, preferably 0.1 to 1.7 mol / L. It is preferable that the concentrations of the liquid A and the liquid B are in the above ranges because the reactivity and the operability of the slurry after the reaction are excellent, and the composition of the ceramic raw material powder tends to be uniform. Moreover, the compounding quantity of the precipitating agent (c) in B liquid is not specifically limited.
[0027]
As the contact method, for example, a slurry comprising water and a titanium compound (a) is continuously supplied into the reactor, and the slurry containing the precipitate (e) generated is continuously contacted so as to be sequentially discharged. A treatment method may be used, or a treatment method in which the slurry containing the precipitate (e) in the reaction vessel is replaced every time the precipitate (e) is produced is contacted intermittently by so-called batch treatment.
[0028]
The contact time is usually 30 seconds or longer, preferably 1 to 10 minutes. A contact time of less than 30 seconds is not preferable because it is difficult to obtain a titanium-based perovskite ceramic powder that is fine and has little variation in particle size. Further, in order to sufficiently remove impurities in the produced titanium-based perovskite ceramic powder, the contact time is preferably as long as possible within the above range.
[0029]
Moreover, contact temperature is 0-100 degreeC normally, Preferably it is 20-80 degreeC, More preferably, it is 20-50 degreeC. Here, the contact temperature means the average temperature of the entire mixture existing when the titanium compound (a), the soluble metal salt (b) and the precipitating agent (c) are contacted in water. When the contact temperature is within this range, the lower the contact treatment temperature, the smaller the particle size of the titanium-based perovskite ceramic raw material powder obtained, which is preferable.
[0030]
If there is a possibility that two or more of the titanium compound (a), the soluble metal salt (b), or the precipitant (c) may react to produce an acid component such as hydrochloric acid or hydrogen sulfide, An alkali agent may be added to at least one of the titanium compound (a), the soluble metal salt (b) and the precipitant (c). Examples of the alkali agent include sodium hydroxide and ammonia. The amount of the alkali agent added is preferably equal to or greater than the amount of the hardly soluble metal compound (d) to be produced. Here, an equivalent means the quantity from which the normality of the slightly soluble metal compound (d) to produce | generate and an alkali agent becomes equal. If the alkali agent is added in an equivalent amount or more, the pH of the solution becomes 7 or more when the hardly soluble metal compound (d) is produced, and thus the hardly soluble metal compound (d) that is easily dissolved in the acidic region is difficult to dissolve. preferable.
[0031]
Examples of the method for adding the alkali agent include, for example, an embodiment in which the alkali agent is added to the titanium compound (a) -containing aqueous slurry, an embodiment in which the alkali agent is added to the soluble metal salt (b) -containing solution, and a precipitant (c). The aspect etc. which add an alkaline agent to a containing solution are mentioned. The addition of the alkali agent can be carried out by neutralizing the alkali agent and the raw material liquid such as the titanium compound (a) -containing aqueous slurry, the soluble metal salt (b) -containing solution, or the precipitant (c) -containing solution. Perform in combinations that do not occur.
[0032]
In addition, when it becomes the combination which mixes with a raw material liquid and produces a neutralization reaction, the addition of an alkaline agent may be performed as follows. That is, when the raw material soluble metal salt (b) and the alkali agent cause a neutralization reaction, for example, the alkali agent is added to either the titanium compound (a) -containing aqueous slurry or the precipitant (c) -containing solution. A method is mentioned. In the case where the precipitant (c) and the alkali agent cause a neutralization reaction, for example, there is a method of adding the alkali agent to either the titanium compound (a) -containing aqueous slurry or the soluble metal salt (b) -containing solution. Can be mentioned.
[0033]
In the first step, first, in water, the soluble metal salt (b) and the precipitating agent (c) react to form a hardly soluble metal compound (d), and then the hardly soluble metal compound (d) is a granular medium. By (f), a shearing force and a frictional force are applied to refine the structure. Next, the finely divided slightly soluble metal compound (d) is deposited on the surface of the titanium compound (a) to form a coated titanium compound. For this reason, the precipitate (e) obtained in the first step contains the coated titanium compound, specifically, it consists only of the coated titanium compound, or deposited on the surface of the titanium compound (a). It is a mixture of a finely divided slightly soluble metal compound (d) and a coated titanium compound, which are free without being released. It is preferable that the precipitate (e) is appropriately filtered, washed and dried to obtain a solid of the precipitate (e). The precipitate (e) is used in the second step.
[0034]
Examples of the reaction apparatus used in the first step include an apparatus capable of bringing the granular medium (f) into contact with the granular medium (f) flowing in water at a high speed. For example, the reaction container and the reaction container A mixing stirrer having a stirrer that stirs the inside (hereinafter also referred to as “first reactor”), a reaction vessel having an inlet and an outlet, a stirrer that stirs the reaction vessel, and the reaction Examples thereof include a mixing and stirring device (hereinafter also referred to as “second reaction device”) having a media separation device provided in a vessel and retaining the granular medium (f) in the reaction vessel. The first reactor is suitable when the contact treatment is intermittently performed by batch processing, and the second reactor is suitable when the contact treatment is continuously processed. Examples of the second reaction apparatus include a wet dispersion pulverization apparatus, and specifically a bead mill apparatus. In addition, when using a bead mill apparatus, the said granular medium (f) is used as a bead used for this apparatus.
[0035]
The bead mill apparatus will be specifically described with reference to FIG. FIG. 1 is a diagram schematically illustrating an example of a bead mill apparatus. The reaction apparatus 1 includes a stirring blade portion 1b having a structure in which a large number of screw type impellers are coaxially fitted to a stirring main shaft, a stirring blade drive portion 1e that drives the stirring blade portion 1b, and the stirring blade portion 1b as an outer periphery of the impeller. A rotating cylinder 1a that converges with a small gap between them and rotates at a lower speed than the impeller in the opposite direction to the stirring blade 1b, inlets 1g and 1f provided on the inlet side of the rotating cylinder 1a, and a rotating cylinder A discharge port 1h provided on the outlet side of 1a and a media separating device 1d disposed in the vicinity of the discharge port 1h in the rotary cylinder 1a are provided. As the media separator 1d, for example, a filter cloth, a gap separator, a screen separator, a centrifugal separator, or the like is used.
[0036]
A preferred example of the method of continuously contacting the first step using the bead mill apparatus shown in FIG. 1 and the action in the first step will be specifically described. First, A liquid is stored in the 1st raw material storage tank 2 connected via the inlet 1g and the pump P1. On the other hand, B liquid is stored in the 2nd raw material storage tank 3 connected via the inlet 1f and the pump P2. Next, after the granular medium (f) is charged into the rotary cylinder 1a from the inlet 1g, the liquid A is introduced into the rotary cylinder 1a from the inlet 1g by using the pump P1, and the rotary cylinder 1a and the stirring blades are introduced. The part 1b is driven to cause the mixture of the liquid A and the granular medium (f) to flow at high speed. At this time, the mixture takes a predetermined time in the rotating cylinder 1a and is separated into the granular medium (f) and the liquid A by the media separating device 1d, and the granular medium (f) stays in the rotating cylinder 1a. The liquid A is discharged from the discharge port 1h so that the contact treatment can be continuously performed. However, the liquid A discharged from the discharge port 1h is introduced into a tank other than the product storage tank 4 (not shown) so as not to be mixed with the slurry containing the precipitate (e) after contact.
[0037]
Next, after connecting the discharge port 1h and the product storage tank 4 so that the discharge from the discharge port 1h is introduced into the product storage tank 4, the B liquid in the second raw material storage tank 3 in this state Is introduced into the rotating cylinder 1a from the inlet 1f, and the liquid A and the liquid B are brought into contact with each other in a state where the granular medium (f) flows at high speed. d) precipitates, and a precipitate (e) is obtained from the hardly soluble metal compound (d) and the titanium compound (a). Since the hardly soluble metal compound (d) is refined by applying a shearing force and a frictional force by the granular medium (f) flowing at a high speed from the moment of precipitation, the refined hardly soluble metal compound (d) Deposited on the surface of the titanium compound (a), a coated titanium compound having a fine and small variation in particle size is formed.
[0038]
The precipitate (e) obtained in the first step is usually composed only of a coated titanium compound. However, when there is a finely divided slightly soluble metal compound (d) that is free without being deposited on the surface of the titanium compound (a), the finely divided hardly soluble metal compound (d) is also precipitated together with the coated titanium compound. Form (e). Even if the coated titanium compound and the refined slightly soluble metal compound (d) are mixed in the precipitate (e), the coated titanium compound is a titanium-based perovskite ceramic raw material powder during firing in the second step. There is no particular problem because the components in the sparingly soluble metal compound (d) are taken into the titanium-based perovskite ceramic raw material powder. In addition, even if the material derived from the poorly soluble metal compound (d) is left free from the titanium-based perovskite ceramic raw material powder after firing, there is no particular problem because it can be removed by washing with an acid or the like. .
[0039]
After completion of the contact treatment under the predetermined conditions, a mixture containing the precipitate (e) and the granular medium (f) is obtained in the rotating cylinder 1a. The mixture is separated into a slurry containing the granular medium (f) and the precipitate (e) by the media separation device 1d, and the granular medium (f) stays in the rotating cylinder 1a and contains the precipitate (e). Is discharged to the product storage tank 4 from the discharge port 1h. The slurry containing the precipitate (e) in the product storage tank 4 is appropriately filtered, washed and dried to obtain a solid of the precipitate (e). The solid of the precipitate (e) is used in the second step.
[0040]
Further, in the first step, the contact treatment is performed by dissolving at least one element selected from the group consisting of rare earth elements, Bi, Zn, Mn, Al, Co, V, Nb, Ni, Cr, Fe, Mg, and Si. When carried out in the presence of the compound (g), it is preferable because it can give reduction resistance to the ceramic raw material powder, adjust the temperature characteristics of the resulting product, and further improve the reliability of the electrical properties of the resulting product. . Here, the rare earth element is at least one selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. is there. Examples of the soluble compound (g) used in the present invention include hydroxides, nitrates, chlorides, sulfide salts, oxalates and carboxylates containing these elements, and silica sol and sodium silicate. It is done. The soluble compound (g) can be used alone or in combination of two or more thereof. In the first step, when the soluble compound (g) and the precipitating agent (c) are brought into contact with each other, the inclusion of the rare earth element, Bi, etc. in the soluble compound (g) further improves the reduction resistance, temperature characteristics and reliability. An excellent highly functional hardly soluble metal compound (h) is produced, and the highly functional hardly soluble metal compound (h) is uniformly deposited on the surface of the titanium compound (a) together with the hardly soluble metal compound (d). It is possible to impart reduction resistance to the raw material powder, adjust the temperature characteristics, and further improve the reliability of the ceramic raw material powder.
[0041]
In the first step, in order to perform the contact treatment in the presence of the soluble compound (g), for example, by the time of the contact treatment, the soluble compound (g) is converted into the titanium compound (a), the soluble metal salt (b), A method of mixing with at least one of the precipitant (c) or the granular medium (f) is used. The mixing order of the titanium compound (a) and the like and the soluble compound (g) at the time of contacting is not particularly limited. However, A liquid is prepared without compounding soluble compound (g), except that A liquid is prepared using a slurry in which soluble compound (g) is further blended with titanium compound (a) and soluble metal salt (b). If the order is the same as that in the case of preparing the solution A, it is preferable for the same reason as in the case of preparing the solution A without blending the soluble compound (g).
[0042]
When the contact treatment is carried out in the presence of a soluble compound (g), it is soluble in the total amount of water, titanium compound (a), soluble metal salt (b), precipitant (c) and soluble compound (g) at the time of contact. The compounding amount of the compound (g) can be arbitrarily set according to the dielectric properties required for the ceramic raw material powder to be produced, and is actually included in the soluble compound (g) among the above elements such as rare earth elements and Bi. The total number of moles converted to the above is usually 0.001 to 0.1 mol / L, preferably 0.003 to 0.05 mol / L. Further, the compounding amount of the titanium compound (a), the soluble metal salt (b) and the precipitating agent (c) with respect to the total amount of the titanium compound (a) and the like is the above numerical range when the soluble compound (g) is not compounded. It is the same.
[0043]
Moreover, when a soluble compound (g) is mix | blended with A liquid and a contact is performed using A liquid or B liquid, the compounding quantity of the soluble compound (g) in A liquid is 0.001-0.1 normally. Mol / L, preferably 0.003 to 0.05 mol / L. Moreover, the compounding quantity of the titanium compound (a) and soluble metal salt (b) in A liquid is the same as the said numerical range when not mix | blending a soluble compound (g). Moreover, the compounding quantity of the precipitating agent (c) in B liquid is not specifically limited.
[0044]
When the contact treatment is carried out in the presence of the soluble compound (g), the contact method, contact time, contact temperature, the kind of alkaline agent blended, if necessary, the addition amount, the addition method, etc. ).
[0045]
The second step is a step of firing the precipitate (e) obtained in the first step to obtain a titanium-based perovskite ceramic raw material powder. The precipitate (e) may be calcined and may or may not contain moisture, but if it is a solid that is substantially free of moisture after being filtered, washed and dried, it can be efficiently used. Since baking can be performed, it is preferable.
[0046]
The firing temperature in firing the precipitate (e) is usually 700 to 1200 ° C, preferably 900 to 1100 ° C. The reason for this is that when the firing temperature is less than 700 ° C., the thermal decomposition of the titanium compound (a) and the hardly soluble metal compound (d) is insufficient and the conversion to the perovskite crystal structure is likely to be insufficient. This is because if the temperature exceeds 1200 ° C., the powder tends to become coarse due to particle growth, which is not preferable. Moreover, baking time is 1 to 40 hours normally, Preferably it is 5 to 30 hours. In the present invention, the firing under the above conditions may be repeated many times. After firing, if necessary, it is pulverized by an air pulverizer or the like to obtain a titanium-based perovskite ceramic raw material powder.
[0047]
If necessary, after completion of the second step, an excess of Ca, Ba, Sr or Pb compounds released from the titanium-based perovskite ceramic raw material powder is removed by washing with acid, followed by washing with water and drying. Thus, a highly pure titanium-based perovskite ceramic raw material powder can be obtained.
[0048]
The titanium-based perovskite ceramic raw material powder thus obtained is ABO. ₃ This is a titanium-based perovskite ceramic powder in which Ca, Ba, Sr or Pb is arranged at the A site of the type perovskite and Ti is arranged at the B site. In addition, the titanium-based perovskite ceramic raw material powder obtained in the present invention has an average particle size x determined by electron microscope observation of usually 0.1 to 1 μm, preferably 0.3 to 0.8 μm. Also, BET specific surface area is 1-20m ² / g, preferably 2-15m ² / g. The particle size variation σ / x is usually 0.1 to 0.3, preferably 0.15 to 0.25, and the particle size variation is extremely small. In σ / x, σ indicates a standard deviation. Since the titanium-based perovskite ceramic raw material powder obtained in the present invention has the above properties, it is suitable for use in electronic parts such as piezoelectric materials, optoelectronic materials, dielectric materials, semiconductors, and sensors.
[0049]
The titanium-based perovskite ceramic raw material powder obtained in the present invention can be used as a raw material for producing a multilayer capacitor. For example, first, the titanium-based perovskite-type ceramic raw material powder and a conventionally known compounding agent such as an additive, an organic binder, a plasticizer, and a dispersing agent are mixed and dispersed to form a slurry. Molding to obtain a ceramic sheet. Next, a conductive paste for forming an internal electrode is printed on one surface of the ceramic sheet, and after drying, a plurality of ceramic sheets are laminated and then pressed in the thickness direction to form a laminate. Further, the laminate is heat-treated to remove the binder, and is fired to obtain a fired body. Thereafter, an In—Ga paste, Ni paste, Ag paste, nickel alloy paste, copper paste, copper alloy paste or the like is applied to this sintered body and baked, whereby a multilayer capacitor can be obtained.
[0050]
In addition, the titanium-based perovskite ceramic raw material powder obtained in the present invention is prepared by blending the barium titanate or barium titanate dielectric obtained in the present invention with a resin such as epoxy resin, polyester resin, polyimide resin, etc. It can be suitably used for materials such as printed wiring boards and multilayer printed wiring boards as sheets, resin films, adhesives and the like. The ceramic raw material powder is composed of a dielectric material for an EL element, a co-material for suppressing a shrinkage difference between the internal electrode and the dielectric layer, a base material for an electrode ceramic circuit board or a glass ceramic circuit board, and a circuit peripheral material. It can be suitably used as a raw material, a catalyst used in reactions such as exhaust gas removal and chemical synthesis, and a surface modifier for printing toner that imparts an antistatic effect and a cleaning effect.
[0051]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.
[0052]
Example 1
<First step>
Barium chloride (BaCl) is added to 500 L of demineralized water. ₂ ・ 2H ₂ O) After dissolving 110.0 kg, a solution obtained by mixing and dispersing 36.3 kg of titanium dioxide fine powder (Toho Titanium Co., Ltd., product name: HT0510, average particle size 0.49 μm) was designated as Liquid A. On the other hand, B solution was prepared by dissolving 36.8 kg of 25% aqueous ammonia and 44 kg of ammonium bicarbonate in 500 L of demineralized water. A liquid is supplied at a flow rate of 470 ml / min to a bead mill apparatus (Ashizawa Co., Ltd., model: Pearl Mill RL type) charged with beads used as a granular medium, and further, B liquid is supplied to the bead mill apparatus at a flow rate of 490 ml / min. The reaction was performed at 20 ° C. The processing conditions of the bead mill apparatus are as follows.
・ Vessel effective amount; 5L
・ Used beads: Zirconia (particle size: 1mm)
・ Bead filling rate: 85%
・ Bead filling amount: 15 kg
・ Agitating blade; disc type
Disk peripheral speed: 10m / sec
・ Processing time: 2 minutes
[0053]
Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 36 hours with a box-type dryer. Next, the dried product was pulverized with a roll mill.
[0054]
<Second step>
The pulverized product after the first step was charged into a shuttle kiln and baked at 1000 ° C. for 17 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. The obtained fired product was analyzed with a fluorescent X-ray analyzer, and TiO ₂ Having a composition of 34.2% by weight and BaO; 65.8% by weight, it was confirmed that the fired product obtained by the X-ray diffraction method was barium titanate. Further, the average particle size x, the BET specific surface area, and the particle size variation σ / x were determined for the fired product. The results are shown in Table 1. In addition, the average particle diameter x is an average value when the particle diameter of 200 or more particles arbitrarily extracted when the sample is observed with an electron microscope at a magnification of 20000 times is measured. Σ is a standard deviation.
[0055]
Example 2
<First step>
Barium chloride (BaCl) is added to 500 L of demineralized water. ₂ ・ 2H ₂ O) 103.3 kg and strontium chloride (SrCl ₂ ・ 6H ₂ O) After 11.0 kg was completely dissolved, 37.2 kg of titanium dioxide (Toho Titanium Co., Ltd., product name: HT0510, average particle size 0.49 μm) was mixed and dispersed, and the solution A was obtained. On the other hand, liquid B was prepared by dissolving 40.0 kg of 25% aqueous ammonia and 48.1 kg of ammonium bicarbonate in 500 L of demineralized water. Next, A liquid was supplied to the bead mill apparatus set to the same conditions as Example 1 with the flow volume of 480 ml /, and B liquid was further supplied to the bead mill apparatus with the flow volume of 500 ml / min, and reaction was performed at 20 degreeC. Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 36 hours with a box-type dryer. Next, the dried product was pulverized with a roll mill.
[0056]
<Second step>
The pulverized product after the first step was charged into a shuttle kiln and baked at 1000 ° C. for 17 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. The obtained fired product was analyzed with a fluorescent X-ray spectrometer, and TiO ₂ 34.2% by weight, BaO; 60.4% by weight, SrO; 4.54% by weight, and a fired product obtained by X-ray diffractometry (Ba _0.9 ・ Sr _0.1 ) TiO ₃ It was confirmed that it was barium strontium zirconate. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 1.
[0057]
Example 3
To 500L of demineralized water, calcium chloride (CaCl ₂ ・ 2H ₂ O) After 114.4 kg was dissolved, a solution obtained by mixing and dispersing 62.0 kg of fine powder of titanium dioxide (Toho Titanium Co., Ltd., product name: HS0510, average particle size 0.49 μm) was designated as Liquid A. On the other hand, liquid B was prepared by dissolving 63 kg of 25% aqueous ammonia and 75.6 kg of ammonium bicarbonate in 500 L of demineralized water. Next, the liquid A was supplied at a flow rate of 500 ml / min to the bead mill apparatus set under the same conditions as in Example 1, and the liquid B was further supplied to the bead mill apparatus at a flow rate of 550 ml / min to carry out the reaction at 20 ° C. . Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 36 hours with a box-type dryer. Next, the dried product was pulverized with a roll mill.
[0058]
<Second step>
The pulverized product after the first step was placed in a shuttle kiln and baked at 1100 ° C. for 17 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. The obtained fired product was analyzed with a fluorescent X-ray analyzer, and TiO ₂ 58.76% by weight, CaO; 41.12% by weight, and the calcined product obtained by the X-ray diffraction method is CaTiO. ₃ Of calcium titanate. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 1.
[0059]
Example 4
<First step>
Barium chloride (BaCl) is added to 500 L of demineralized water. ₂ ・ 2H ₂ O) After dissolving 110.0 kg, titanyl sulfate (TiSO), which is an intermediate product in the production of sulfuric acid method titanium dioxide ₄ ) Titanium hydrate or metatitanic acid (TiO (OH)) produced by hydrolysis of ₂ ) 44.5kg (TiO ₂ The solution A was equivalent to 36.3 g in terms of conversion; the average particle size of 0.3 μm was mixed and dispersed. On the other hand, B solution was prepared by dissolving 36.8 kg of 25% aqueous ammonia and 44 kg of ammonium bicarbonate in 500 L of demineralized water. Next, the liquid A was supplied at a flow rate of 450 ml / min to the bead mill apparatus set under the same conditions as in Example 1, and the liquid B was further supplied to the bead mill apparatus at a flow rate of 480 ml / min to carry out the reaction at 50 ° C. . Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 36 hours with a box-type dryer. Next, the dried product was pulverized with a roll mill.
[0060]
<Second step>
The pulverized product after the first step was placed in a shuttle kiln and baked at 1100 ° C. for 20 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. The obtained fired product was analyzed with a fluorescent X-ray analyzer, and TiO ₂ 34.2% by weight, BaO; 65.4% by weight, and it was confirmed that the fired product obtained by the X-ray diffraction method was barium titanate. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 1.
[0061]
Example 5
<First step>
Barium chloride (BaCl) is added to 500 L of demineralized water. ₂ ・ 2H ₂ O) After dissolving 110.0 kg, a solution obtained by mixing and dispersing 36.3 kg of titanium dioxide fine powder (Toho Titanium Co., Ltd., product name: HT1701, average particle size 0.34 μm) was designated as Liquid A. On the other hand, B solution was prepared by dissolving 122.1 kg of ammonium citrate in 500 L of demineralized water. Next, A liquid was supplied to the bead mill apparatus set to the same conditions as Example 1 with the flow volume of 450 ml / min, and also B liquid was supplied to the bead mill apparatus with the flow volume of 470 ml / min, and reaction was performed at 50 degreeC. . Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 36 hours with a box-type dryer. Next, the dried product was pulverized with a roll mill.
[0062]
<Second step>
The pulverized product after the first step was placed in a shuttle kiln and baked at 1100 ° C. for 20 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. The obtained fired product was analyzed with a fluorescent X-ray analyzer, and TiO ₂ 34.3% by weight, BaO; 65.4% by weight. It was confirmed that the fired product obtained by the X-ray diffraction method was barium titanate. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 1.
[0063]
Example 6
<First step>
Barium chloride (BaCl) is added to 500 L of demineralized water. ₂ ・ 2H ₂ O) After dissolving 110.0 kg, a solution obtained by mixing and dispersing 36.3 kg of titanium dioxide fine powder (Toho Titanium Co., Ltd., product name: HT1701, average particle size 0.34 μm) was designated as Liquid A. On the other hand, B solution was prepared by dissolving 60.9 kg of sodium oxalate in 500 L of demineralized water. Next, A liquid was supplied to the bead mill apparatus set to the same conditions as Example 1 with the flow volume of 500 ml / min, B liquid was further supplied to the bead mill apparatus with the flow volume of 500 ml / min, and reaction was performed at 50 degreeC. . Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 36 hours with a box-type dryer. Next, the dried product was pulverized with a roll mill.
[0064]
<Second step>
The pulverized product after the first step was placed in a shuttle kiln and baked at 1100 ° C. for 20 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. The obtained fired product was analyzed with a fluorescent X-ray analyzer, and TiO ₂ It was confirmed that the fired product having a composition of 34.3% by weight and BaO; 65.5% by weight and obtained by the X-ray diffraction method was barium titanate. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 1.
[0065]
Example 7
<First step>
Barium hydroxide (Ba (OH)) was added to 500 L of demineralized water. ₂ ・ 8H ₂ O) After dissolving 14.2 kg, titanyl sulfate (TiSO), which is an intermediate product in the production of sulfuric acid method titanium dioxide ₄ ) Titanium hydrate or metatitanic acid (TiO (OH)) produced by hydrolysis of ₂ 4.4 kg (TiO ₂ A liquid corresponding to 3.6 kg in terms of conversion and having an average particle diameter of 0.5 μm was mixed and dispersed. Next, liquid A was supplied at a flow rate of 500 ml / min to the bead mill apparatus set under the same conditions as in Example 1, and further carbon dioxide gas was supplied to the bead mill apparatus at a flow rate of 1.6 L / min and reacted at 20 ° C. Went. Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 20 hours with a box dryer. Next, the dried product was pulverized with a roll mill.
[0066]
<Second step>
The pulverized product after the first step was placed in a shuttle kiln and baked at 1100 ° C. for 20 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. The obtained fired product was analyzed with a fluorescent X-ray analyzer, and TiO ₂ 34.3% by weight, BaO; 65.4% by weight. It was confirmed that the fired product obtained by the X-ray diffraction method was barium titanate. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 1.
[0067]
Example 8
Barium chloride (BaCl) is added to 500 L of demineralized water. ₂ ・ 2H ₂ O) 102.0 kg, calcium chloride (CaCl · 2H) ₂ O) 5.24 kg, manganese chloride (MnCl ₂ ・ 4H ₂ O) 2.34 kg, bismuth chloride (BiCl ₃ ) After dissolving 3.52 kg, a solution obtained by mixing and dispersing 36.2 kg of fine powder of titanium dioxide (Toho Titanium Co., Ltd., product name: HT1701, average particle size 0.34 μm) was designated as Liquid A. On the other hand, a solution obtained by dissolving 36.8 kg of 25% aqueous ammonia and 44 kg of ammonium bicarbonate in 500 L of demineralized water was designated as solution B. Next, A liquid was supplied to the bead mill apparatus set to the same conditions as Example 1 with the flow volume of 500 ml / min, B liquid was further supplied to the bead mill apparatus with the flow volume of 500 ml / min, and reaction was performed at 50 degreeC. . Next, the precipitate collected by filtration with a filter press was washed with about 1000 L of demineralized water, and then dried at 120 ° C. for 36 hours with a box-type dryer. Next, the dried product was pulverized with a roll mill.
[0068]
<Second step>
The pulverized product after the first step was placed in a shuttle kiln and baked at 1100 ° C. for 20 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. When the obtained fired product was analyzed with a fluorescent X-ray analyzer, BaTiO was used. ₃ 91.9% by weight, CaTiO ₃ 4.85% by weight, MnO ₂ 0.65% by weight, Bi ₂ O ₃ A composition of 2.6% by weight. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 1.
[0069]
[Table 1]

[0070]
Comparative Examples 1-3
BET specific surface area is 8.2m ² / G, 12.3m ² / G of two types of commercially available BaCO ₃ Powder and BET specific surface area of 7.7m ² / G, 18.4m ² / G of two commercially available TiO ₂ Powder was prepared. Next, BaCO ₃ And TiO ₂ These raw material powders were weighed so that the molar ratio was 1: 1. Next, BaCO shown in Table 2 ₃ And TiO ₂ In a ball mill together with water and zirconia balls (1.5φ) and thoroughly mixed for 15 hours in a wet manner. The resulting slurry was placed in a dryer and dried at 150 ° C. to obtain a mixed powder. . Next, the dried product was pulverized with a roll mill. This pulverized product was placed in a shuttle kiln and baked at 1100 ° C. for 24 hours. Next, the fired product was pulverized with a roll mill and further pulverized with a jet mill to obtain a baked product. It was confirmed that the fired product obtained by the X-ray diffraction method was barium titanate. The average particle size x, BET specific surface area, and particle size variation σ / x were determined for the fired product. The results are shown in Table 2.
[0071]
[Table 2]

[0072]
From the results of Tables 1 and 2, it can be seen that the titanium-based perovskite ceramic raw material powder obtained by the production method according to the present invention is fine and has very little variation in particle size distribution.
[0073]
【The invention's effect】
According to the method for producing a titanium-based perovskite ceramic raw material powder according to the present invention, it is possible to obtain a fine powder having extremely small variation in particle size distribution. The titanium-based perovskite-type ceramic raw material powder can be suitably used for functional ceramics, particularly ceramic sheets that require thinning.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an example of a bead mill apparatus.
[Explanation of symbols]
1 Bead mill equipment
1a Rotating tube (vessel)
1b Stir blade
1c Zirconia beads
1d media separator
1e Stirring blade drive
1f, 1g inlet
1h outlet
2 First raw material storage tank
3 Second raw material storage tank
4 Product storage tank
P1, P2 pump

Claims (4)

At least one selected from the group consisting of titanium compound (a) selected from titanium oxide or hydrous titanium oxide and having a compounding amount of 0.01 to 3 mol / L in terms of Ti, and Ca, Ba, Sr and Pb. A soluble metal salt (b) of a seed element, a precipitant (c) that reacts with the soluble metal salt (b) to form a hardly soluble metal compound (d), a particle size of 0.05 to 10 mm and a reaction A first step of obtaining a precipitate (e) by contacting a granular medium (f) having a filling rate of 40 to 95% in the apparatus in a state where the granular medium (f) flows at high speed in water; And a second step of firing the precipitate (e) to obtain a titanium-based perovskite-type ceramic raw material powder, and a method for producing a titanium-based perovskite-type ceramic raw material powder. The method for producing a titanium-based perovskite ceramic raw material powder according to claim 1, wherein the compounding amount of the titanium compound (a) is 0.1 to 3 mol / L in terms of Ti. The precipitant (c) is selected from the group consisting of ammonium bicarbonate, ammonium carbonate, sodium carbonate, carbon dioxide, oxalic acid, ammonium oxalate, citric acid, sodium citrate, ammonium citrate, tartaric acid, sodium tartrate and ammonium tartrate. 3. The method for producing a titanium-based perovskite-type ceramic raw material powder according to claim 1 or 2, wherein the at least one compound is selected. The contact treatment in the first step is a soluble compound of at least one element selected from the group consisting of rare earth elements, Bi, Zn, Mn, Al, Co, V, Nb, Ni, Cr, Fe, Mg, and Si ( The method for producing a titanium-based perovskite ceramic raw material powder according to any one of claims 1 to 3, wherein the production is performed in the presence of g).

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